1. Field of the Invention
The present invention relates to an antenna device and a reception device for receiving a radio wave signal, and a radio wave timepiece for receiving a standard radio wave containing a time code.
2. Description of Related Art
In general, various antennas such as a linear antenna, a wire-wound bar antenna, a planar antenna, etc. are known. A wire-wound bar antenna is used for a radio wave timepiece or the like receiving a standard radio wave because it is necessary to mount an antenna in a small timepiece body.
General antennas such as the linear antenna, the wire-wound bar antenna, etc. are restricted in miniaturization. That is because the linear antenna is required to have a length which is matched with a reception frequency band, and the wire-wound bar antenna is lowered in effective Q value (the sharpness of the resonance peak) and sensitivity due to an effect of demagnetizing field when the core thereof is short.
Furthermore, because the wire-would bar antenna, when a metal element are close to it, induces an eddy current there due to variation of a magnetic flux occurring in the winding coil and the core, and the sensitivity of the antenna is remarkably lowered due to the induced eddy current.